Because of advances in micro-circuitry and multimedia technology, digital cameras are now in widespread used. High-end portable electronic devices, such as mobile phones and Personal Digital Assistants (PDAs), are being developed to be increasingly multi-functional. Many of these portable electronic devices are popularly equipped with digital cameras. To facilitate portability, such portable electronic devices tend to be compact, slim, and light. Accordingly, digital cameras incorporated in the portable electronic devices have also been required to be reduced in size and weight, yet to remain cost-effective.
Referring to FIG. 5, a typical digital camera module 1 includes a lens module 2, a lens holder 3, and an image sensor chip 4. The lens module 2 includes a barrel 21 and a lens 22 received in the barrel 21. The barrel 21 is partially received in and is threadingly engaged with the lens holder 3. An IR (infra-red) cut filter 6 is adhered to a top surface 40 of the image sensor chip 4 to protect the image sensor chip 4 against damage from IR light. The image sensor chip 4 is typically mounted on a printed circuit board 5. The image sensor chip 4 has a photosensitive area 41 formed on the top surface 40 thereof. The photosensitive area 41 is configured for receiving light signals transmitted through the lens module 2. A plurality of chip pads is formed on the top surface 40 for surrounding the photosensitive area 41. A plurality of board pads is formed on the printed circuit board 5 to electrically connect to the corresponding chip pads via wires. A plurality of elements 7 is formed on the periphery of the printed circuit board 5 around the board pads. The lens holder 3 is mounted on the printed circuit board 5 so that the image sensor chip 4, the chip pads, the board pads, and the wires are received therein.
In the camera module 1, the printed circuit board 5 needs to provide sufficient space not only for the image sensor chip 4, the driver 7, and the wires but the lens holder 3 as well. To minimize the size and volume of the camera module 1 to a certain degree, an end portion 32 of the lens holder 3 is made thin. However, such a thin lens holder 3 is not easily manufactured by an injection molding method. This difficulty results in a relatively high cost. As such, the camera module 1 has not proven to be economically suitable for slim and compact electronic products.
What is needed, therefore, is a camera module that is both compact and economical to produce.